Hobbs joined Carat in 1995 and rose through the ranks, becoming broadcast manager in 1997, broadcast director in 2002 and head of media in 2005, before being appointed head of planning and integration in 2006.

Horler said: "Amnet had a great launch year in 2012 and continues to grow rapidly. It has the potential to help clients reinvent how they build their brands through media, and in Steve and Sacha, we have a highly experienced and strategic leadership team that will make Amnet even more compelling a proposition for our clients in 2013."